I discovered Home Assistant in 2017 and have been slowly adding to it since then.
I run a dedicated Ubuntu 18.04.3 LTS server Intel(R) Core(TM) i7-2600 CPU @ 3.40GHz with 16 gig of ram (This is my main server - I run other things on here as well as Home Assistant)
My setup is a Python Virtual Environment utilising this guide.
I use GitHub Actions. When I commit a change to this repo it kicks off an automatic test of the config using a Home Assistant environment. See the config here.
It's very powerful and can run parallel tests on multiple versions of Python and Home Assistant. I currently test Python 3.7 and 3.8 as well as Home Assistant Stable and Beta versions. This helps me know if my config is going to work on a later version before I upgrade.
My Home Assistant Config